I deposited $30 Sunday into my Coinbase Pro account and made a purchase for $30. With the current market, that purchase is now worth $27.50. When I deposited the $30 I was informed that I could trade instantly but would need to wait 13 days before I could transfer any purchase out of coinbase which isn’t a big deal. However, last night I transferred in a second coin that I was looking to sell and decided not to, I went to transfer the second coin out and Coinbase Pro is holding a portion of the second coin to make up the difference from the drop in value of my $30 purchase. Why would this second coin that was in my wallet not coinbase at the time of the $30 purchase be “held hostage” for the first purchase I made?